How does a volcanic eruption occur? The natural phenomenon that shows us the majesty of our planet and at the same time is a little terrifying.
Our planet works like a well-oiled gear, everything is connected and allows it to behave as a large entity. Perhaps our understanding of dimensions is not enough to fully imagine the Earth working as a single unit, but that is how it behaves. The natural phenomena that arise in it are interconnected with other functions that we cannot see with the naked eye.
Volcanic eruptions are not simple releases of incandescent matter, but go beyond that, from the process for one to occur, to the changes it causes on the planet. To better understand the eruption process of a , you have to look at it from different angles, starting with what lies beneath the earth.
Composition of the Earth
Our planet is made up of various layers, imagine a spherical mass with different coatings of materials that make it giant in size. In addition, the layers present temperature differences, as the center becomes hotter and the outer layers become colder. This is precisely how the Earth is formed.
Inside, there is a layer composed of molten rocks, crystals and gases, at extremely high temperatures, which we call magma. But in the outermost and coldest layers we have what we call tectonic plates. Sometimes, volcanoes form at the edges of these plates, which are escape ducts for the Earth. In other words, when there is a very large pressure due to the increase in temperature in the magma inside the planet, it will have a way of escaping through volcanoes and this is how eruptions occur.
How a volcanic eruption occurs
When there is an increase in temperature elevation in the magma, the pressure inside the Earth increases and it shoots with violent shocks towards the surface through the volcanoes. The shaking caused by the expulsion can be so violent that it sometimes even causes earthquakes and also causes damage to the surrounding area.
As the magma approaches the surface, it loses part of the gases contained in its solution, causing the generation of bubbles inside. Depending on the conditions and behavior of the magma, two forms of volcanic eruptions can arise.
Effusive eruption: If the magma gases are released without altering the pressure, the magma can come to the surface without exploding.
Explosive eruption: If the magma accumulates more pressure, without releasing the gases, then the bubbles will grow inside and the magma will violently fragment, producing an explosion.
When the magma comes out of the volcano’s crater, it stops being called that and becomes lava. When it touches the , it cools and solidifies in different ways. The names of the remains left behind by a volcanic eruption depend on their size, so we have everything from the smallest particles called ash to the largest ones called volcanic bombs.
Volcanic explosiveness index
Now we know that there are different magnitudes of volcanic eruptions, not all of them are the same. To learn more about the subject, experts stipulated what is known as the Volcanic Explosivity Index, which is more or less a kind of Richter scale, but for volcanoes.
It goes from 0 to 8 to measure the strength of the eruptions and like the Richter scale, the increase in values is not linear, but exponential. Thus the difference between each interval represents a tenfold increase in magnitude.
Collateral damage and health effects
The consequences left by a volcanic eruption are severe, the lava has high temperatures so it will melt everything in its path, flora and fauna. This is why populations should stay away from active volcanoes. But this is not the main problem, the really worrying issue is pyroclastic flows, which are violent avalanches of ash, rock and gases that erupt from the volcano.
The main health problems are closely linked to respiratory problems caused by the inhalation of volcanic ash that is capable of traveling long distances. This is why it is important to follow all security measures when we face a situation of this nature.